A few weeks ago, after sharing a meal with the college students at a church in Edwardsville, I was coming out of church with a young student named Taylor. I mentioned one of her hometown stations, WIKK 103.5 (known on the air as 103.5 the Eagle). This inspired me to write this blog entry. The question I have is: "How can I explain my radio hobbies to the layman?" Or, in other words, to someone who isn't aware of the hobby.
First off, there's a term frequently used in the radio hobby: DX. The term DX comes from the telegrapher's abbreviation for "distance". This is commonly used by Morse Code operators. DX also comes from algebra, with D = distance, and X = any number. A person who listens for distant stations in the radio broadcast bands, watches for distant over-the-air television stations and talking to ("working") distant Amateur Radio (Ham) radio operators, is commonly referred to as a DXer. I've been a DXer since I was 15 years old.
Many people listen to FM radio these days. If you were hitting the "scan" feature on the FM and it comes up on a distant station, even if it was from your hometown, there's a good chance you would be amazed, shocked and/or surprised. How does this happen? Maybe this DX Central page, FM DXing, will help you understand how you picked up that distant FM station. This covers the basics, signal propagation methods and equipment you'll need to partake in this portion of the hobby. For example, the propagation method I heard Taylor's hometown station by is called tropospheric ducting, or tropospheric enhancement. Newton, IL is 135 airline miles from my listening post in Hazelwood, MO. The FM broadcast band in North America is between 88 and 108 MHz, which falls in the very high frequency (VHF) band. An excellent listing of North American FM broadcast stations is the WTFDA FM Database. I am a member of WTFDA.
Now, what if you were doing a scan or rescan on your television set, or tuner, and several of the signals you hit in that scan is from outside your area? Today's digital TV stations operate on VHF and UHF channels in the United States. There are three different bands for over-the-air (OTA) television, VHF-Low (Channels 2 through 6, below the FM broadcast band),VHF-High (Channels 7 through 13, above the FM broadcast band) and UHF (Channels 14 through 36). An explanation of OTA TV frequencies in the Americas can be found in this article from Wikipedia. Signal propagation on the bands in which OTA TV operates can be explained through this article in TV Technology. Tropospheric enhancement, or tropospheric ducting, is the most common form of signal propagation on OTA TV, especially on high-band VHF and UHF frequencies. More often than not, the channel the station operates on is not the same as the channel number the station uses. This channel is called a virtual channel. For example, my local CBS affiliate, KMOV, operates on UHF Channel 24, but uses virtual channel 4 (the station's former analog channel). Below are video captures of distant TV stations logged at my Hazelwood, MO monitoring station, using a Hauppaugue Win-TV HVR dongle, to which I connected a digital TV tuner, with the signal fed from an outdoor antenna.
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| WKYT Lexington, KY, operating on UHF Channel 21.4 (virtual channel 27.4), received at a distance of 330 airline miles in July 2021 |
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| WLFI Lafayette, IN, operating on channel 11.1 (virtual channel 18.1), received at a distance of 225 airline miles in July 2021 |
In your parents' or grandparents' day, they more than likely listened to an AM radio station. This band falls well below the FM broadcast band, between 530 kHz and 1.71 MHz. Today, you'll find many talk radio stations on this band, as well as Christian and ethnic radio stations and various forms of music. During the day, depending on frequency ground conductivity, AM radio signals generally have regional coverage. At night, the signal characteristics of AM stations change dramatically. During hours of darkness, signals come in from other parts of the country. On most nights, I can hear such diverse stations as WSM Nashville, TN at 650 on the AM dial (the home of the Grand Ole Opry), or hear news from other cities from all-news stations like WBBM in Chicago (780) or KYW in Philadelphia (1060). The Federal Communications Commission has an article on their Web site on this topic. The AM DXing Web site provides plenty of information on this part of my hobby. The FCC also puts out a ground conductivity map (more detailed maps can be found on the Internet), which explains how groundwave signals propagate on the AM broadcast band. I started casually listening to distant AM signals in the sixth grade.
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| Ground conductivity map (Source: FCC) |
The impetus I had for buying my first shortwave receiver came from a station I heard when I was in the eighth grade. Even with a local station (WRTH, now KFNS) at 590 on the AM dial, I heard a station at 600 on the AM dial with programming that didn't come from the United States or Canada. As it turned out, a high powered station out of Cuba was relaying Radio Moscow's programming to the southeastern United States. I was able to hear a perspective from the other side of the Iron Curtain. A week after I turned 15 years old, I bought a portable receiver with three shortwave broadcast bands, the Citizens' Band and the AM and FM broadcast bands. I was able to hear perspectives on world events from a wider variety of viewpoints, not just the American, Canadian or Soviet viewpoints. Shortwave broadcasting isn't used as much today as it was in the 20th Century. Wikipedia has a detailed article on the medium. Shortwave signal propagation is different than those of AM or FM broadcast band stations; an excellent reference is this article on the Short Wave Info Web site. Many shortwave radio send in reports detailing what they heard to radio stations; an accurate report is rewarded with a card from the station. Many have scenes from the country of origin. Below are several examples.
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| This aerial view of Vatican City is from Vatican Radio for a 1998 reception. |
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| This card from the Far East Broadcasting Company in the Philippines is for a 1999 reception. (Both were received at Hazelwood.) |
Many are interested in monitoring public service communications on VHF and UHF. These frequencies are where we can find local and regional first responders, transportation and industrial communications. These are also called "the action frequencies". An excellent reference is Radio Reference, which lists these frequencies, as well as giving tips for purchasing equipment to receive public service communications. The weather radio band (162.400 to 162.550 MHz) falls in this segment; the National Oceanic and Atmospheric Administration (NOAA) has a nationwide network of stations providing the public with weather information all day and all night. You can find information on NOAA Weather Radio can be found at this link.
When I mentioned Amateur Radio in conversation, one of the campus missionaries didn't know what it is. Another club I am a member of is the American Radio Relay League, the national organization supporting the hobby. Amateur Radio Operators are more commonly known as Hams. An excellent starting reference is What is Amateur Radio?, posted on the ARRL's Web site. Another article on the ARRL Web site is Getting Licensed, which details the different classes of Amateur Radio licenses (I hold the highest class license, Amateur Extra). I've been licensed since 1992, before many of my youngest friends were born.
In addition to the Worldwide TV-FM DX Association and the American Radio Relay League, I'm also a member of the North American Shortwave Association and the International Radio Club of America, as well as two local radio clubs, the Lewis and Clark Radio Club and the Saint Louis and Suburban Radio Club.
If you have any other questions about my hobby, feel free to ask me in the reply box below this entry or on Facebook.
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